Aspectos ultra-estruturais dos canais secretores em órgãos vegetativos e reprodutivos de Anacardiaceae

The study assessed phloem canal development and ultra-structure in shoot apices of Spondias dulcis G. Forst., phloematic canal ultra-structure in shoot apices of Tapirira guianensis Aubl., and floral canal ultra-structure and development and fruit canal ultra-structure of the latter specie. The flower and fruit canals of Anacardium humile St.Hil. were also studied ultra-structurally. The canals in shoot apices of S. dulcis show schizo-lysigenous formation and the floral canals of T. guianensis show schizogenous development. Epithelial cells of S. dulcis and T. guianensis canals have rough endoplasmic reticulum, free ribosomes, elongated plastids of several shapes with osmiophilic inclusions and dictyosomes with production of vesicles. Such organelles participate in the secretion of a heterogeneous exudate, which is comprised of hydrophilic and lipophilic substances. The epithelial cells of the fruit of A. humile present elongated plastids with circular membrane system, which are involved in the synthesis of lipophilic substances. The results of the ultra-structural analyses of the epithelial cells corroborate the results previously obtained in a histochemical study. In the histochemical study, lipophilic and hydrophilic substances were identified in the canals of T. guinanensis and S. dulcis and only lipophilic substances were identified in the canals of A. humile. Based on the ultrastructural aspects of the secretory canals of T. guianensis and S. dulcis we concluded that the plastids of the epithelial cells of the two species are different although they produce secretion of similar composition. A new record for the family is the presence of a great number of circular plastids in epithelial cells of the fruit of Anacardium humile. The pattern found in the secretory canals of the studied species is the ecrine type of secretion release.

Neuronal Ceroid-lipofuscinosis with prominent chorea and without visual manifestations: a case report

A case of neuronal ceroid-lipofuscinosis (NCL) is reported in a 11-year-old girl, whose main symptoms were progressive dementia since the age of 4 years and choreic movements since age 10. Seizures, myoclonus and visual deterioration were absent and optic fundi were normal. A cerebral biopsy disclosed two basic types of stored substance in the cytoplasm of neurons: a) severely balloned nerve cells in cortical layers HI and V contained a non-autofluorescent material, which stained with PAS and Sudan Black B in frozen, but not in paraffin sections; ultrastructurally, these neurons showed abundant corpuscles similar to the membranous cytoplasmic bodies of Tay-Sachs disease and, in smaller amounts, also zebra bodies; b) slightly distended or non-distended neurons in all layers contained lipopigment granules, which were autofluorescent, PAS-positive and sudanophil in both frozen and paraffin sections; their ultrastructure was closely comparable to that of lipofuscin. Similar bodies were found in the swollen segments of axons and in a few astrocytes and endothelial cells. The histochemical and ultrastructural demonstration of large amounts of lipopigments allows a presumptive classification of the case as NCL. However, the presence of involuntary movements, the absence of visual disturbances and the unusual ultrastructural features place the patient into a small heterogeneous group within the NCL. A better classification of such unique instances of the disease must await elucidation of the basic enzymatic defects.

Desenvolvimento humano, lazer e educação fisica escolar : o papel do componente ludico da cultura

Universidade Estadual de Campinas. Faculdade de Educação Física

O corpo e seus textos : o estetico, o politico e o pedagogico na dança

Universidade Estadual de Campinas. Faculdade de Educação Física

O setor privado sem fins lucrativos e as políticas públicas de esporte e lazer (2008-2011) = : The non-profitable private sector and the public policies for sport and leisure (2008-2011)

Universidade Estadual de Campinas . Faculdade de Educação Física

Estratégias para individualização de resultados em testes de desempenho

Universidade Estadual de Campinas. Faculdade de Educação Física

Esporte e qualidade de vida : reflexão sociologica

Universidade Estadual de Campinas . Faculdade de Educação Física

T-wave alternans: desempenho clínico, limitações, metodologias de análise

Reconhecer com precisão indivíduos com maior risco imediato de morte súbita cardíaca (MSC) ainda é uma questão em aberto. A natureza fortuita dos eventos cardiovasculares agudos não parece se adequar ao conhecido modelo de indução de taquicardia/fibrilação ventricular por um gatilho em sincronia a um substrato arritmogênico estático. Quanto ao mecanismo da MSC, uma instabilidade elétrica dinâmica explicaria melhor a raridade da associação simultânea de um gatilho certo a um substrato cardíaco apropriado. Diversos estudos tentaram medir essa instabilidade elétrica cardíaca (ou um equivalente válido) em uma sequência de batimentos cardíacos no ECG. Dentre os mecanismos possíveis podemos citar o prolongamento do QT, dispersão do QT, potenciais tardios, alternância de onda T ou T-wave alternans (TWA), e turbulência da frequência cardíaca. Este artigo se atém em particular ao papel da TWA no panorama atual da estratificação de risco cardíaco. Os achados sobre TWA ainda são heterogêneos, variando de um desempenho prognóstico muito bom até um quase nulo, dependendo da população clínica observada e protocolo clínico usado. Para preencher as atuais lacunas no conhecimento sobre TWA, profissionais médicos e pesquisadores devem explorar melhor as características técnicas das diversas tecnologias disponíveis para a avaliação de TWA e atentar ao fato de que os valores de TWA respondem a diversos outros fatores, além de medicamentos. Informações sobre mecanismos celulares e subcelulares da TWA estão fora do escopo deste artigo, mas são referenciados alguns dos principais trabalhos sobre este tópico, com o intuito de auxiliar no entendimento dos conceitos e fatos cobertos neste artigo.

Repair of critical-size defects with autogenous periosteum-derived cells combined with bovine anorganic apatite/collagen: an experimental study in rat calvaria

The aim of this study was to evaluate the bone repair using autogenous periosteum-derived cells (PDC) and bovine anorganic apatite and collagen (HA-COL). PDC from Wistar rats (n=10) were seeded on HA-COL discs and subjected to osteoinduction during 6 days. Critical-size defects in rat calvarias were treated with blood clot (G1), autogenous bone (G2), HA-COL (G3) and HA-COL combined with PDC (G4) (n=40), and then analyzed 1 and 3 months after surgeries. Radiographic analysis exhibited no significant temporal change. G1 and G2 had discrete new marginal bone, but the radiopacity of graft materials in G2, G3 and G4 impaired the detection of osteogenesis. At 3 months, histopathological analysis showed the presence of ossification islets in G1, which was more evident in G2, homogeneous new bone around HA-COL in G3 and heterogeneous new bone around HA-COL in G4 in addition to moderate presence of foreign body cells in G3 and G4. Histomorphometric analysis showed no change in the volume density of xenograft (p>0.05) and bone volume density in G2 was twice greater than in G1 and G4 after 3 months (p<0.05), but similar to G3. The PDC did not increase bone formation in vivo, although the biomaterial alone showed biocompatibility and osteoconduction capacity.

Experimental infections with Paracoccidioides brasiliensis obtained from armadillos: comparison to clinical isolates

Paracoccidioides brasiliensis causes paracoccidioidomycosis (PCM) that is one of the most prevalent systemic human mycoses in Latin America. Armadillos show a high incidence of PCM infection and could, therefore, be a natural reservoir for this fungus. In this study were compared the virulence profiles of isolates obtained from nine-banded armadillos (Dasypus novemcinctus) (PbT1 and PbT4) and isolates from PCM patients (Pb265 and Bt83). Pathogenicity was evaluated by fungal load and analysis of colony morphology. Immunity against the fungus was tested by delayed type hypersensitivity test (DTH) and antibody quantification by ELISA. The higher virulence of PbT1 and PbT4 was suggested by higher fungal load in spleen and lungs. Armadillo isolates and Bt83 presented a cotton-like surface contrasting with the cerebriform appearance of Pb265. All isolates induced cellular and humoral immune responses in infected BALB/c mice. DTH reactions were similarly induced by the four isolates, however, a great variability was observed in specific antibody levels, being the highest ones induced by Bt83 and PbT4. The present work confirms that armadillos harbor P. brasiliensis, whose multiplication and induced immunity in experimentally infected mice are heterogeneous, resembling the behavior of isolates from human PCM. This study reinforces the possibility that armadillos play an important role in the biological cycle of this pathogen.

Alluvial-eolian interaction in a Cambrian rift margin: the Pedra das Torrinhas and Pedra Pintada formations (Guaritas Group, RS)

This work presents a study of selected outcrops from the Pedra das Torrinhas Formation of the Guaritas Group (Cambrian, Camaquã Basin), near the basin bordering Encantadas Fault Zone. The studied succession includes alluvial fan deposits that pass laterally into eolian deposits. Sedimentary facies and architectural element analysis were performed, followed by sedimentary petrography and microscopic porosity analysis, aiming to characterize the porosity of the deposits and its spatial distribution. The main objective was to contribute to a better understanding of the porosity spatial distribution in depositional systems characterized by the interaction between alluvial and eolian processes, with special reference to deposits formed prior to the development of terrestrial plants. Porosity values are related to depositional processes, with higher porosities associated to eolian dune deposits (mean of 8.4%), and lower porosity related to interdunes (mean of 3.4%) and alluvial fans (mean of 4.3%). Architectural elements analysis revealed the spatial relationships of these deposits, a response to the interplay of the eolian and alluvial processes. The integration of porosity data reveals that the interaction of alluvial and eolian processes results in heterogeneous distribution of porosity at the facies association scale. Eolian reworking of alluvial facies increases porosity whereas sheet-flood and other alluvial processes in the interdune areas reduce porosity.

Synthesis of Fe/Ti oxides from a single source alkoxide precursor under inert atmosphere

The heterometal alkoxide [FeCl{Ti2(OPr i)9}] (1) was employed as a single source precursor for the preparation of Fe/Ti oxides under inert atmosphere. Three different synthetic procedures were adopted in the processing of 1, either employing aqueous HNO3 or HCl solutions, or in the absence of mineral acids. Products were characterised by powder X-ray diffractometry, scanning electron microscopy combined with energy dispersive X-ray spectroscopy (SEM/EDS) and Raman, electron paramagnetic resonance (EPR) and Mössbauer spectroscopies. Oxide products contained titanium(IV) and either iron(III) or iron(II), depending on reaction conditions and thermal treatment temperatures. An interesting iron(III)→iron(II) reduction was observed at 1000 ºC in the HNO3-containing system, leading to the detection of ilmenite (FeTiO3). SEM/EDS studies revealed a highly heterogeneous metal distribution in all products, possibly related to the presence of a significant content of carbon and of structural defects (oxygen vacancies) in the solids.

Catalytic enantioselective arylations: boron to zinc exchange as a powerful tool for the generation of transferable aryl groups

The transmetalation between boron and zinc is of great importance for application in organic synthesis, since it allows the formation of new carbon-carbon bonds between organometallic units and electrophiles. The direct arylation of aldehydes or more scarcely ketones, in a catalytic, enantioselective manner using chiral catalysts has been described recently. The enantiomerically enriched diarylmethanols obtained in these reactions are valuable precursors for important bioactive molecules. This review provides a synopsis of this ever-growing field and highlights some of the challenges that still remain.

Uma perspectiva computacional sobre catálise enzimática

Enzymes are extremely efficient catalysts. Here, part of the mechanisms proposed to explain this catalytic power will be compared to quantitative experimental results and computer simulations. Influence of the enzymatic environment over species along the reaction coordinate will be analysed. Concepts of transition state stabilisation and reactant destabilisation will be confronted. Divided site model and near-attack conformation hypotheses will also be discussed. Molecular interactions such as covalent catalysis, general acid-base catalysis, electrostatics, entropic effects, steric hindrance, quantum and dynamical effects will also be analysed as sources of catalysis. Reaction mechanisms, in particular that catalysed by protein tyrosine phosphatases, illustrate the concepts.

Electrocatalytic oxidation of methanol by the [Ru3O(OAc)6(py)2(CH3OH)]3+cluster: improving the metal-ligand electron transfer by accessing the higher oxidation states of a multicentered system

The [Ru3O(Ac)6(py)2(CH3OH)]+ cluster provides an effective electrocatalytic species for the oxidation of methanol under mild conditions. This complex exhibits characteristic electrochemical waves at -1.02, 0.15 and 1.18 V, associated with the Ru3III,II,II/Ru3III,III,II/Ru 3III,III,III /Ru3IV,III,III successive redox couples, respectively. Above 1.7 V, formation of two RuIV centers enhances the 2-electron oxidation of the methanol ligand yielding formaldehyde, in agreement with the theoretical evolution of the HOMO levels as a function of the oxidation states. This work illustrates an important strategy to improve the efficiency of the oxidation catalysis, by using a multicentered redox catalyst and accessing its multiple higher oxidation states.